Can I put frozen meat in a slow cooker?

According to the makers of Crock-Pot, "Frozen meats: Can be cooked in a slow cooker, however, it is best to use the following guidelines: Add at least 1 cup of warm liquid to the stoneware before placing meat in the stoneware. Do not preheat the slow cooker. Cook recipes containing frozen meats for an additional 4 to 6 hours on Low, or an additional 2 hours on High."

I've done it successfully with smaller amounts of meat, but I once cooked a roast that was probably at least 4 pounds without defrosting it and that did not go very well (nothing terrible, but my husband and I both got a bit sick after eating it).

http://amath.colorado.edu/~baldwind/sous-vide.html

is your best source for the ways in which meat can be cooked safely at low temperatures. Look at the tables in section 2 to see how long it takes for tender meat to come directly to temperature at various heats, then later tables for time to pasteurization for meat held at various temperatures (for chicken, table 4.7).

I would tend to recommend against whole chickens in the slow cooker because of the large thickness, but just breast or something should be ok as long as you're on a relatively high setting and you leave it in for at least eleven hours.

Slow cookers now cook at higher temperatures than the original ones. When I was first married, if I cooked frozen meats in my crockpot, the safety of the meat always seemed questionable and I got sick a time or two. With the slow cookers I have purchased in the last ten years, I have been able to cook frozen meat on high without a problem and even low heat cooks hot. In fact, I have burned food trying to cook foods on keep warm (not recommended by manufacturer).

USDA guidlines indicate that you should not put frozen meat directly into the crockpot. That being said I have no problems putting frozen london broil into my slowcooker on low for 10+ hours. Makes for an easy no fuss, no thought meal and I have had no ill effects.

Personally I would not be comfortable doing a whole frozen chicken because of how dense they are and how long they take to defrost.

Crock pot cookbooks says yes. Should be boiling water so can equalize heat. I've cooked both frozen chicken and frozen beef, 9 hours on low. Done for years for large parties and family.

I think the safest way to be sure is to microwave a little first

I have cooked frozen chicken breast in the crock pot for years. No one has ever been sick from eating it. I make pulled buffalo chicken for 5 hours on low and then 2 hours on high. I think the important rule to remember is to cook the meat to the recommended USDA temperature for whatever meat you cook.

Who do you trust, the US govt, or a person who really cooks?

As long as the pot is covered, and the meat is not previously contaminated, this should be totally safe. Safer than, say, thawing meat in water, then grilling it. Or at least equally safe. There are other factors involved.

To minimize risk, I just thawed the meat in a microwave a little, but not enough for it to begin to brown on the outside. That seems to be a fair compromise.